1. Field of the Invention
Disclosed herein is a high velocity ammunition round that more particularly is sub-caliber with a high density forward portion and a lower density aft portion. Optionally, a sustainer propellant or a base-bleed propellant may be contained within the aft portion.
2. Description of the Related Art
A significant, and uncontrollable, source of error in the accuracy of a long range sniper round is wind. Other sources of error include the effect of gravity during a long time of flight, variations in gun powder charge and drag. Drag causes the bullet velocity to decrease which increases the time of flight to a target. Types of drag that act on a bullet are wave drag (the drag force resulting from aerodynamic shock waves), skin friction drag (the friction between the airstream and the surface of the projectile) and base drag (a vacuum effect at the back of the bullet).
U.S. Pat. No. 6,070,532, titled “High Accuracy Projectile,” discloses a projectile having improved accuracy when fired over long ranges that is formed from a monolithic block of a copper alloy. U.S. Pat. No. 5,297,492, titled “Armor Piercing Fin-Stabilized Discarding Sabot Tracer Projectile,” discloses an armor piercing projectile having a fin stabilized sub-caliber high density rod penetrator and a blind cavity extending inward from an aft end of the projectile. This blind cavity is filled with a tracer composition. Both U.S. Pat. No. 6,070,532 and U.S. Pat. No. 5,297,492 are incorporated by reference in their entireties herein.